Patent Ductus Arteriosus in the Premature Infant: A Clinical Dilemma

The ductus arteriosus (DA) connects the main pulmonary artery and the aorta in the fetus. Although the term infant DA almost always closes in the first three days of postnatal life, that of the preterm infant can be present for weeks to months. The frequency of diagnosis and rate of complications due to patent ductus arteriosus (PDA) are inversely proportional to gestational age. This vascular connection between pulmonary and systemic circulations can lead to the “stealing” of blood from systemic organs supplied by the aorta. Furthermore, with left-to-right shunting across the DA, the preterm lung is challenged with increased pulmonary blood flow. Although these complications can be serious, many infants with a PDA are asymptomatic. Despite monumental advances in neonatal care over the last 20 years, the best approach to management of PDA in preterm infants remains unclear. Clinical practice still varies widely with regard to treatment.